Unmediated communication in games with complete and incomplete information

• 成果类型: Article
• 署名作者: Gerardi, D
• 署名单位: Yale University
• 刊物名称: JOURNAL OF ECONOMIC THEORY
• ISSN/ISSBN: 0022-0531
• DOI: 10.1016/S0022-0531(03)00124-8
• 发表日期: 2004
• 页码: 104-131
• 关键词: communication; correlated equilibrium; communication equilibrium; Sequential equilibrium; revelation principle

摘要

We study the effects of adding unmediated communication to static, finite games of complete and incomplete information. We characterize S-U (G), the set of outcomes of a game G, that are induced by sequential equilibria of cheap talk extensions. A cheap talk extension of G is an extensive-form game in which players communicate before playing G. A reliable mediator is not available and players exchange private or public messages that do not affect directly their payoffs. We first show that if G is a game of complete information with five or more players and rational parameters, then S-U(G) coincides with the set of correlated equilibria of G. Next, we demonstrate that if G is a game of incomplete information with at least five players, rational parameters and full support (i.e., all profiles of types have positive probability), then S-U(G) is equal to the set of communication equilibria of G. (C) 2003 Elsevier Inc. All rights reserved.